Questions tagged [collision]
This tag is for questions relating to collision which is the interaction between two or more bodies that results in physical contact and an exchange of momentum between the bodies involved. When it happens, kinetic energy is often exchanged between the molecules’ translational motion and their internal degrees of freedom.
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The Time That 2 Masses Will Collide Due To Newtonian Gravity [closed]
My friend and I have been wracking our heads with this one for the past 3 hours...
We have 2 point masses, $m$ and $M$ in a perfect world separated by radius r. Starting from rest, they both begin to ...
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Why doesn't matter pass through other matter if atoms are 99.999% empty space?
The ghostly passage of one body through another is obviously out of the question if the continuum assumption were valid, but we know that at the micro, nano, pico levels (and beyond) this is not even ...
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How can momentum but not energy be conserved in an inelastic collision?
In inelastic collisions, kinetic energy changes, so the velocities of the objects also change.
So how is momentum conserved in inelastic collisions?
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Why are ions and electrons at different temperatures in a plasma?
In plasmas, the collision rate among ions or electrons is much larger than the collision rate between ions and electrons. Why is that so?
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Would it help if you jump inside a free falling elevator?
Imagine you're trapped inside a free falling elevator. Would you decrease your impact impulse by jumping during the fall? When?
user145
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Can linear momentum be conserved before and after collision in the presence of an external force?
I'm a physics tutor for 11th and 12th grade students. I taught my students that momentum is conserved only when the net external force on the system is zero. But in the books we are following, ...
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Elastic collision between two circles [duplicate]
I am trying to calculate the final velocities of two equal mass 2-dimensional circles after an elastic collision. I have tried to figure it out using formulas I know from high school physics, but ...
user99752
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What is the relative speed of two near-light speed particles headed towards each other? [duplicate]
I understand that nothing can move faster than light due to time dilation. I want to build upon my understanding of Einstein's theory of Special Relativity, so I came up with this hypothetical problem ...
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Can black holes actually merge?
If time stops at the event horizon, can we ever detect two black holes merging? In other words, if you are a short distance away, would you encounter a spherically symmetric gravitational field, or a ...
Ze Kraggash
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Could we use particle colliders as fusion generators?
So I know the basic gist is that fusion power's main issue is sustaining the fusion. I also know that there are two methods. The Torus method and the laser method. The torus magnetically contains ...
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Is two cars colliding at 50mph the same as one car colliding into a wall at 100 mph?
I was watching a youtube video the other day where an economist said that he challenged his physics professor on this question back when he was in school. His professor said each scenario is the same, ...
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How and why will the Milky Way collide with the Andromeda galaxy?
Hubble's law says that the universe is expanding. How come the Milky Way and the Andromeda galaxies are on a collision course? How will they end up colliding with each other?
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Formalism to deal with discontinuous potentials in classical mechanics (hard wall, hard spheres)
It seems to me that Hamiltonian formalism does not suit well for problems involving instantaneous change of momentum, like particle collisions with hard wall or hard sphere gas model. At least I could ...
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Physics of simple collisions
I'm building a physics simulator for a graphics course, and so far I have it implementing gravitational and Coulomb forces. I want to add collisions next, but I'm not exactly sure how to go about ...
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Collisions between an object and a wall
Is momentum conserved when an object bounces back against a wall? The wall doesn’t move, but the object moves in the opposite direction. Assume this is an ideal, elastic collision.
If, initially, the ...
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